U.S. Pat. No. 7,494,303 discloses an indexable cutting insert having a trigon shape for tangentially mounting in a milling cutter body. The cutting insert is provided with support surfaces for abutment against a pocket of the milling cutter body. The support surfaces project outwardly from sides of the cutting insert with an axial extension that is smaller or equal to half the thickness of the cutting insert. The outwardly projecting support surfaces may have an adverse effect on chip development and evacuation.